Avocado oil comprises a significant proportion of the fruit of the avocado. The fruit of the avocado is generically referred to as "avocado" or as "an avocado" herein. This principally comprises avocado oil, seed, skin, fruit pulp and water. The oil itself has many uses, among them as an ingredient in salad dressings, in various foods, in cosmetics, and in the manufacture of soap. Various free fatty acids and vitamins are also found in the avocado.
The avocado itself, and avocado oil, have a widespread and growing appeal. This market appears to be limited only by availability of the fruit, and to a lesser extent by its cost. Because of the value of the land on which the avocado trees are grown, the lead time required to bring new trees into production, the care the trees require, their susceptibility to troublesome and disastrous diseases, especially viruses, and their susceptibility to the vagaries of the weather, it is a major decision whether to start a new orchard, and how to price, process and distribute the fruit and its by-products which can be produced.
One thing which can properly be stated is that whenever avocado oil is produced, there appears to be a market for it. In view of this fact, there have been many efforts made to extract the oil at least cost and in best quality. Depending on the market for fresh avocados and for processed avocado pulp in various forms such as frozen guacamole, the sale of avocado oil can often comprise an important source of income. Furthermore, it can be extracted from fruit which is of insufficient quality to sell as such, or which is in excess of market demands, thereby reducing at least some of the grower's risks.
Some problems with known extraction processes for avocado oil are (a) the use of hot water and enzymes to aid in the separation of pulp from the oil, adding to the processing problems because they tend to degrade the quality of the oil and cause dificulties in disposing of water process water, (b) boiling of the fruit to release the oil, resulting in low recovery and sometimes degraded oil, and (c) the use of centrifuges or of squeezing processes of low sophistication, which result in low oil yields.
It is an object of this invention to provide for efficient extraction of avocado oil at moderate temperatures, and for extracting raw oil with the addition only of herbaceous silicious material that is readily retained during extraction that facilitates the extraction of the oil.
It is another object of this invention to obtain from the process some of the values which are often discarded with the seeds and skins.